[The use of seatbelts and child seats in drivers and passengers of motor vehicles in four metropolitan areas in Mexico].

OBJECTIVES To estimate the rate of seatbelt and child seat use in drivers and passengers of motor vehicles in four metropolitan areas in Mexico (Guadalajara, León, Monterrey and Mexico City). To evaluate the impact of the Mexican Initiative for Road Safety (IMESEVI) in this respect. MATERIAL AND METHODS Data were collected at the start of IMESEVI (June 2008) and one year after the program's implementation (October 2009) in the four participating metropolitan areas. In particular, the use of seatbelts and child seats was observed in occupants of automobiles, station wagons, and light trucks. The sample included 28,412 (pre) and 52,274 (post) individuals, of which 1,454 (pre) and 1,679 (post) were younger than five years old. The data analysis was based on a hierarchical logistic model. RESULTS Globally, the probability of using either safety device is 46% (95% CI: 43-49%) at baseline and 52% (95% CI: 48-55%) at the post measurement, with large differences, though, among the four participating metropolitan areas. Factors that significantly affect their use include the individual's position in the vehicle, the type and age of the vehicle, and the individual's sex. Child seat use is very limited. At baseline, about 17% (95% CI: 11-25%) of children below five years old travelled in a special seat, with this number increasing to 26% (95% CI: 19-34%) after the implementation of IMESEVI. Child seat use for children above four years is virtually nonexistent. CONCLUSIONS Continued efforts are required to raise the public awareness of the importance of using safety devices, especially for passengers in the back of the car as well as with respect to the use of adapted seats for small children.